For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningInstallation Procedure
Position the front end upper tie bar (1) on the vehicle.
Verify the fit of the front end upper tie bar.
Clamp the front end upper tie bar into position.
Braze accordingly.
Braze accordingly.
Grind down weld seams as needed for related panels and components.
Clean a ...
Removal Procedure
Warning: Refer to Approved Equipment for Collision Repair Warning in
the Preface section.
Disable the SIR System. Refer to SIR Disabling
and Enabling.
Disconnect the negative battery cable. Refer to Battery Negative Cable
Disconnection and Connection.
Remove all related panels ...
Air/Wind Noise
Special Tools
CH-39570 Chassis Ear
GE-41416 Ultrasonic Leak Detector
Warning: Refer to Assistant Driving Warning in the Preface section.
To analyze a reported windnoise condition, test drive the vehicle to
determine the origin of the noise.
Choose a regular route with smooth and strai ...